* [PATCH 1/3] spi/s3c64xx: Log error interrupts
@ 2011-12-05 21:01 Mark Brown
2011-12-05 21:01 ` [PATCH 2/3] spi/s3c64xx: Convert to dev_pm_ops Mark Brown
2011-12-05 21:01 ` [PATCH 3/3] spi/s3c64xx: Implement runtime PM support Mark Brown
0 siblings, 2 replies; 6+ messages in thread
From: Mark Brown @ 2011-12-05 21:01 UTC (permalink / raw)
To: Linus Walleij, Kukjin Kim, Grant Likely
Cc: spi-devel-general, linux-samsung-soc, patches, Mark Brown
Although the hardware supports interrupts we're not currently using them
at all since for small transfers the overhead is greater than that for
busy waiting and for large transfers we have interrupts from the DMA.
This means that if the hardware reports an error (especially one which
might not stall transfer) we might miss it.
Take a first pass at dealing with such errors by enabling the interrupt
if we can and logging the errors if they happen. Ideally we'd report the
error via the affected transfer but since we're in master mode it's very
difficult to trigger errors at present and this code is much simpler.
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
---
drivers/spi/spi-s3c64xx.c | 56 +++++++++++++++++++++++++++++++++++++++++++-
1 files changed, 54 insertions(+), 2 deletions(-)
diff --git a/drivers/spi/spi-s3c64xx.c b/drivers/spi/spi-s3c64xx.c
index dcf7e10..9b16406 100644
--- a/drivers/spi/spi-s3c64xx.c
+++ b/drivers/spi/spi-s3c64xx.c
@@ -20,6 +20,7 @@
#include <linux/init.h>
#include <linux/module.h>
#include <linux/workqueue.h>
+#include <linux/interrupt.h>
#include <linux/delay.h>
#include <linux/clk.h>
#include <linux/dma-mapping.h>
@@ -153,6 +154,7 @@ struct s3c64xx_spi_dma_data {
* @tx_dmach: Controller's DMA channel for Tx.
* @sfr_start: BUS address of SPI controller regs.
* @regs: Pointer to ioremap'ed controller registers.
+ * @irq: interrupt
* @xfer_completion: To indicate completion of xfer task.
* @cur_mode: Stores the active configuration of the controller.
* @cur_bpw: Stores the active bits per word settings.
@@ -930,6 +932,33 @@ setup_exit:
return err;
}
+static irqreturn_t s3c64xx_spi_irq(int irq, void *data)
+{
+ struct s3c64xx_spi_driver_data *sdd = data;
+ struct spi_master *spi = sdd->master;
+ unsigned int val;
+
+ val = readl(sdd->regs + S3C64XX_SPI_PENDING_CLR);
+
+ val &= S3C64XX_SPI_PND_RX_OVERRUN_CLR |
+ S3C64XX_SPI_PND_RX_UNDERRUN_CLR |
+ S3C64XX_SPI_PND_TX_OVERRUN_CLR |
+ S3C64XX_SPI_PND_TX_UNDERRUN_CLR;
+
+ writel(val, sdd->regs + S3C64XX_SPI_PENDING_CLR);
+
+ if (val & S3C64XX_SPI_PND_RX_OVERRUN_CLR)
+ dev_err(&spi->dev, "RX overrun\n");
+ if (val & S3C64XX_SPI_PND_RX_UNDERRUN_CLR)
+ dev_err(&spi->dev, "RX underrun\n");
+ if (val & S3C64XX_SPI_PND_TX_OVERRUN_CLR)
+ dev_err(&spi->dev, "TX overrun\n");
+ if (val & S3C64XX_SPI_PND_TX_UNDERRUN_CLR)
+ dev_err(&spi->dev, "TX underrun\n");
+
+ return IRQ_HANDLED;
+}
+
static void s3c64xx_spi_hwinit(struct s3c64xx_spi_driver_data *sdd, int channel)
{
struct s3c64xx_spi_info *sci = sdd->cntrlr_info;
@@ -970,7 +999,7 @@ static int __init s3c64xx_spi_probe(struct platform_device *pdev)
struct s3c64xx_spi_driver_data *sdd;
struct s3c64xx_spi_info *sci;
struct spi_master *master;
- int ret;
+ int ret, irq;
char clk_name[16];
if (pdev->id < 0) {
@@ -1006,6 +1035,12 @@ static int __init s3c64xx_spi_probe(struct platform_device *pdev)
return -ENXIO;
}
+ irq = platform_get_irq(pdev, 0);
+ if (irq < 0) {
+ dev_warn(&pdev->dev, "Failed to get IRQ: %d\n", irq);
+ return irq;
+ }
+
master = spi_alloc_master(&pdev->dev,
sizeof(struct s3c64xx_spi_driver_data));
if (master == NULL) {
@@ -1100,10 +1135,21 @@ static int __init s3c64xx_spi_probe(struct platform_device *pdev)
INIT_WORK(&sdd->work, s3c64xx_spi_work);
INIT_LIST_HEAD(&sdd->queue);
+ ret = request_irq(irq, s3c64xx_spi_irq, 0, "spi-s3c64xx", sdd);
+ if (ret != 0) {
+ dev_err(&pdev->dev, "Failed to request IRQ %d: %d\n",
+ irq, ret);
+ goto err8;
+ }
+
+ writel(S3C64XX_SPI_INT_RX_OVERRUN_EN | S3C64XX_SPI_INT_RX_UNDERRUN_EN |
+ S3C64XX_SPI_INT_TX_OVERRUN_EN | S3C64XX_SPI_INT_TX_UNDERRUN_EN,
+ sdd->regs + S3C64XX_SPI_INT_EN);
+
if (spi_register_master(master)) {
dev_err(&pdev->dev, "cannot register SPI master\n");
ret = -EBUSY;
- goto err8;
+ goto err9;
}
dev_dbg(&pdev->dev, "Samsung SoC SPI Driver loaded for Bus SPI-%d "
@@ -1115,6 +1161,8 @@ static int __init s3c64xx_spi_probe(struct platform_device *pdev)
return 0;
+err9:
+ free_irq(irq, sdd);
err8:
destroy_workqueue(sdd->workqueue);
err7:
@@ -1153,6 +1201,10 @@ static int s3c64xx_spi_remove(struct platform_device *pdev)
spi_unregister_master(master);
+ writel(0, sdd->regs + S3C64XX_SPI_INT_EN);
+
+ free_irq(platform_get_irq(pdev, 0), sdd);
+
destroy_workqueue(sdd->workqueue);
clk_disable(sdd->src_clk);
--
1.7.7.3
^ permalink raw reply related [flat|nested] 6+ messages in thread* [PATCH 2/3] spi/s3c64xx: Convert to dev_pm_ops
2011-12-05 21:01 [PATCH 1/3] spi/s3c64xx: Log error interrupts Mark Brown
@ 2011-12-05 21:01 ` Mark Brown
2011-12-05 21:01 ` [PATCH 3/3] spi/s3c64xx: Implement runtime PM support Mark Brown
1 sibling, 0 replies; 6+ messages in thread
From: Mark Brown @ 2011-12-05 21:01 UTC (permalink / raw)
To: Linus Walleij, Kukjin Kim, Grant Likely
Cc: spi-devel-general, linux-samsung-soc, patches, Mark Brown
In preparation for the addition of runtime PM ops.
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
---
drivers/spi/spi-s3c64xx.c | 19 ++++++++++---------
1 files changed, 10 insertions(+), 9 deletions(-)
diff --git a/drivers/spi/spi-s3c64xx.c b/drivers/spi/spi-s3c64xx.c
index 9b16406..d0c70f2 100644
--- a/drivers/spi/spi-s3c64xx.c
+++ b/drivers/spi/spi-s3c64xx.c
@@ -1226,9 +1226,9 @@ static int s3c64xx_spi_remove(struct platform_device *pdev)
}
#ifdef CONFIG_PM
-static int s3c64xx_spi_suspend(struct platform_device *pdev, pm_message_t state)
+static int s3c64xx_spi_suspend(struct device *dev)
{
- struct spi_master *master = spi_master_get(platform_get_drvdata(pdev));
+ struct spi_master *master = spi_master_get(dev_get_drvdata(dev));
struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(master);
unsigned long flags;
@@ -1248,9 +1248,10 @@ static int s3c64xx_spi_suspend(struct platform_device *pdev, pm_message_t state)
return 0;
}
-static int s3c64xx_spi_resume(struct platform_device *pdev)
+static int s3c64xx_spi_resume(struct device *dev)
{
- struct spi_master *master = spi_master_get(platform_get_drvdata(pdev));
+ struct platform_device *pdev = to_platform_device(dev);
+ struct spi_master *master = spi_master_get(dev_get_drvdata(dev));
struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(master);
struct s3c64xx_spi_info *sci = sdd->cntrlr_info;
unsigned long flags;
@@ -1269,19 +1270,19 @@ static int s3c64xx_spi_resume(struct platform_device *pdev)
return 0;
}
-#else
-#define s3c64xx_spi_suspend NULL
-#define s3c64xx_spi_resume NULL
#endif /* CONFIG_PM */
+static const struct dev_pm_ops s3c64xx_spi_pm = {
+ SET_SYSTEM_SLEEP_PM_OPS(s3c64xx_spi_suspend, s3c64xx_spi_resume)
+};
+
static struct platform_driver s3c64xx_spi_driver = {
.driver = {
.name = "s3c64xx-spi",
.owner = THIS_MODULE,
+ .pm = &s3c64xx_spi_pm,
},
.remove = s3c64xx_spi_remove,
- .suspend = s3c64xx_spi_suspend,
- .resume = s3c64xx_spi_resume,
};
MODULE_ALIAS("platform:s3c64xx-spi");
--
1.7.7.3
^ permalink raw reply related [flat|nested] 6+ messages in thread* [PATCH 3/3] spi/s3c64xx: Implement runtime PM support
2011-12-05 21:01 [PATCH 1/3] spi/s3c64xx: Log error interrupts Mark Brown
2011-12-05 21:01 ` [PATCH 2/3] spi/s3c64xx: Convert to dev_pm_ops Mark Brown
@ 2011-12-05 21:01 ` Mark Brown
1 sibling, 0 replies; 6+ messages in thread
From: Mark Brown @ 2011-12-05 21:01 UTC (permalink / raw)
To: Linus Walleij, Kukjin Kim, Grant Likely
Cc: spi-devel-general, linux-samsung-soc, patches, Mark Brown
Enable and disable the clocks to the SPI controller using runtime PM. This
serves the dual purpose of reducing power consumption a little and letting
the core know when the device is idle.
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
---
drivers/spi/spi-s3c64xx.c | 39 +++++++++++++++++++++++++++++++++++++++
1 files changed, 39 insertions(+), 0 deletions(-)
diff --git a/drivers/spi/spi-s3c64xx.c b/drivers/spi/spi-s3c64xx.c
index d0c70f2..b899af66 100644
--- a/drivers/spi/spi-s3c64xx.c
+++ b/drivers/spi/spi-s3c64xx.c
@@ -25,6 +25,7 @@
#include <linux/clk.h>
#include <linux/dma-mapping.h>
#include <linux/platform_device.h>
+#include <linux/pm_runtime.h>
#include <linux/spi/spi.h>
#include <mach/dma.h>
@@ -782,6 +783,8 @@ static void s3c64xx_spi_work(struct work_struct *work)
while (!acquire_dma(sdd))
msleep(10);
+ pm_runtime_get_sync(&sdd->pdev->dev);
+
spin_lock_irqsave(&sdd->lock, flags);
while (!list_empty(&sdd->queue)
@@ -810,6 +813,8 @@ static void s3c64xx_spi_work(struct work_struct *work)
/* Free DMA channels */
sdd->ops->release(sdd->rx_dma.ch, &s3c64xx_spi_dma_client);
sdd->ops->release(sdd->tx_dma.ch, &s3c64xx_spi_dma_client);
+
+ pm_runtime_put(&sdd->pdev->dev);
}
static int s3c64xx_spi_transfer(struct spi_device *spi,
@@ -892,6 +897,8 @@ static int s3c64xx_spi_setup(struct spi_device *spi)
goto setup_exit;
}
+ pm_runtime_get_sync(&sdd->pdev->dev);
+
/* Check if we can provide the requested rate */
if (!sci->clk_from_cmu) {
u32 psr, speed;
@@ -924,6 +931,8 @@ static int s3c64xx_spi_setup(struct spi_device *spi)
err = -EINVAL;
}
+ pm_runtime_put(&sdd->pdev->dev);
+
setup_exit:
/* setup() returns with device de-selected */
@@ -1159,6 +1168,8 @@ static int __init s3c64xx_spi_probe(struct platform_device *pdev)
mem_res->end, mem_res->start,
sdd->rx_dma.dmach, sdd->tx_dma.dmach);
+ pm_runtime_enable(&pdev->dev);
+
return 0;
err9:
@@ -1192,6 +1203,8 @@ static int s3c64xx_spi_remove(struct platform_device *pdev)
struct resource *mem_res;
unsigned long flags;
+ pm_runtime_disable(&pdev->dev);
+
spin_lock_irqsave(&sdd->lock, flags);
sdd->state |= SUSPND;
spin_unlock_irqrestore(&sdd->lock, flags);
@@ -1272,8 +1285,34 @@ static int s3c64xx_spi_resume(struct device *dev)
}
#endif /* CONFIG_PM */
+#ifdef CONFIG_PM_RUNTIME
+static int s3c64xx_spi_runtime_suspend(struct device *dev)
+{
+ struct spi_master *master = spi_master_get(dev_get_drvdata(dev));
+ struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(master);
+
+ clk_disable(sdd->clk);
+ clk_disable(sdd->src_clk);
+
+ return 0;
+}
+
+static int s3c64xx_spi_runtime_resume(struct device *dev)
+{
+ struct spi_master *master = spi_master_get(dev_get_drvdata(dev));
+ struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(master);
+
+ clk_enable(sdd->src_clk);
+ clk_enable(sdd->clk);
+
+ return 0;
+}
+#endif /* CONFIG_PM_RUNTIME */
+
static const struct dev_pm_ops s3c64xx_spi_pm = {
SET_SYSTEM_SLEEP_PM_OPS(s3c64xx_spi_suspend, s3c64xx_spi_resume)
+ SET_RUNTIME_PM_OPS(s3c64xx_spi_runtime_suspend,
+ s3c64xx_spi_runtime_resume, NULL)
};
static struct platform_driver s3c64xx_spi_driver = {
--
1.7.7.3
^ permalink raw reply related [flat|nested] 6+ messages in thread
* [PATCH 0/3] spi/s3c64xx diagnostic and PM updates
@ 2012-01-21 13:23 Mark Brown
2012-01-21 13:24 ` [PATCH 1/3] spi/s3c64xx: Log error interrupts Mark Brown
0 siblings, 1 reply; 6+ messages in thread
From: Mark Brown @ 2012-01-21 13:23 UTC (permalink / raw)
To: Grant Likely, Linus Walleij; +Cc: linux-samsung-soc, spi-devel-general
The following changes since commit 805a6af8dba5dfdd35ec35dc52ec0122400b2610:
Linux 3.2 (2012-01-04 15:55:44 -0800)
are available in the git repository at:
git://git.kernel.org/pub/scm/linux/kernel/git/broonie/misc.git spi/s3c64xx
They've all been posted several times before but seem to have got
dropped on the floor somewhere along the line.
Mark Brown (3):
spi/s3c64xx: Log error interrupts
spi/s3c64xx: Convert to dev_pm_ops
spi/s3c64xx: Implement runtime PM support
drivers/spi/spi-s3c64xx.c | 115 ++++++++++++++++++++++++++++++++++++++++----
1 files changed, 104 insertions(+), 11 deletions(-)
^ permalink raw reply [flat|nested] 6+ messages in thread* [PATCH 1/3] spi/s3c64xx: Log error interrupts
2012-01-21 13:23 [PATCH 0/3] spi/s3c64xx diagnostic and PM updates Mark Brown
@ 2012-01-21 13:24 ` Mark Brown
2012-01-21 13:24 ` [PATCH 3/3] spi/s3c64xx: Implement runtime PM support Mark Brown
0 siblings, 1 reply; 6+ messages in thread
From: Mark Brown @ 2012-01-21 13:24 UTC (permalink / raw)
To: Grant Likely, Linus Walleij
Cc: spi-devel-general, linux-samsung-soc, Mark Brown
Although the hardware supports interrupts we're not currently using them
at all since for small transfers the overhead is greater than that for
busy waiting and for large transfers we have interrupts from the DMA.
This means that if the hardware reports an error (especially one which
might not stall transfer) we might miss it.
Take a first pass at dealing with such errors by enabling the interrupt
if we can and logging the errors if they happen. Ideally we'd report the
error via the affected transfer but since we're in master mode it's very
difficult to trigger errors at present and this code is much simpler.
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
---
drivers/spi/spi-s3c64xx.c | 57 +++++++++++++++++++++++++++++++++++++++++++-
1 files changed, 55 insertions(+), 2 deletions(-)
diff --git a/drivers/spi/spi-s3c64xx.c b/drivers/spi/spi-s3c64xx.c
index 019a716..d56066b 100644
--- a/drivers/spi/spi-s3c64xx.c
+++ b/drivers/spi/spi-s3c64xx.c
@@ -20,6 +20,7 @@
#include <linux/init.h>
#include <linux/module.h>
#include <linux/workqueue.h>
+#include <linux/interrupt.h>
#include <linux/delay.h>
#include <linux/clk.h>
#include <linux/dma-mapping.h>
@@ -153,6 +154,7 @@ struct s3c64xx_spi_dma_data {
* @tx_dmach: Controller's DMA channel for Tx.
* @sfr_start: BUS address of SPI controller regs.
* @regs: Pointer to ioremap'ed controller registers.
+ * @irq: interrupt
* @xfer_completion: To indicate completion of xfer task.
* @cur_mode: Stores the active configuration of the controller.
* @cur_bpw: Stores the active bits per word settings.
@@ -930,6 +932,33 @@ setup_exit:
return err;
}
+static irqreturn_t s3c64xx_spi_irq(int irq, void *data)
+{
+ struct s3c64xx_spi_driver_data *sdd = data;
+ struct spi_master *spi = sdd->master;
+ unsigned int val;
+
+ val = readl(sdd->regs + S3C64XX_SPI_PENDING_CLR);
+
+ val &= S3C64XX_SPI_PND_RX_OVERRUN_CLR |
+ S3C64XX_SPI_PND_RX_UNDERRUN_CLR |
+ S3C64XX_SPI_PND_TX_OVERRUN_CLR |
+ S3C64XX_SPI_PND_TX_UNDERRUN_CLR;
+
+ writel(val, sdd->regs + S3C64XX_SPI_PENDING_CLR);
+
+ if (val & S3C64XX_SPI_PND_RX_OVERRUN_CLR)
+ dev_err(&spi->dev, "RX overrun\n");
+ if (val & S3C64XX_SPI_PND_RX_UNDERRUN_CLR)
+ dev_err(&spi->dev, "RX underrun\n");
+ if (val & S3C64XX_SPI_PND_TX_OVERRUN_CLR)
+ dev_err(&spi->dev, "TX overrun\n");
+ if (val & S3C64XX_SPI_PND_TX_UNDERRUN_CLR)
+ dev_err(&spi->dev, "TX underrun\n");
+
+ return IRQ_HANDLED;
+}
+
static void s3c64xx_spi_hwinit(struct s3c64xx_spi_driver_data *sdd, int channel)
{
struct s3c64xx_spi_info *sci = sdd->cntrlr_info;
@@ -970,7 +999,8 @@ static int __init s3c64xx_spi_probe(struct platform_device *pdev)
struct s3c64xx_spi_driver_data *sdd;
struct s3c64xx_spi_info *sci;
struct spi_master *master;
- int ret;
+ int ret, irq;
+ char clk_name[16];
if (pdev->id < 0) {
dev_err(&pdev->dev,
@@ -1010,6 +1040,12 @@ static int __init s3c64xx_spi_probe(struct platform_device *pdev)
return -ENXIO;
}
+ irq = platform_get_irq(pdev, 0);
+ if (irq < 0) {
+ dev_warn(&pdev->dev, "Failed to get IRQ: %d\n", irq);
+ return irq;
+ }
+
master = spi_alloc_master(&pdev->dev,
sizeof(struct s3c64xx_spi_driver_data));
if (master == NULL) {
@@ -1104,10 +1140,21 @@ static int __init s3c64xx_spi_probe(struct platform_device *pdev)
INIT_WORK(&sdd->work, s3c64xx_spi_work);
INIT_LIST_HEAD(&sdd->queue);
+ ret = request_irq(irq, s3c64xx_spi_irq, 0, "spi-s3c64xx", sdd);
+ if (ret != 0) {
+ dev_err(&pdev->dev, "Failed to request IRQ %d: %d\n",
+ irq, ret);
+ goto err8;
+ }
+
+ writel(S3C64XX_SPI_INT_RX_OVERRUN_EN | S3C64XX_SPI_INT_RX_UNDERRUN_EN |
+ S3C64XX_SPI_INT_TX_OVERRUN_EN | S3C64XX_SPI_INT_TX_UNDERRUN_EN,
+ sdd->regs + S3C64XX_SPI_INT_EN);
+
if (spi_register_master(master)) {
dev_err(&pdev->dev, "cannot register SPI master\n");
ret = -EBUSY;
- goto err8;
+ goto err9;
}
dev_dbg(&pdev->dev, "Samsung SoC SPI Driver loaded for Bus SPI-%d "
@@ -1119,6 +1166,8 @@ static int __init s3c64xx_spi_probe(struct platform_device *pdev)
return 0;
+err9:
+ free_irq(irq, sdd);
err8:
destroy_workqueue(sdd->workqueue);
err7:
@@ -1157,6 +1206,10 @@ static int s3c64xx_spi_remove(struct platform_device *pdev)
spi_unregister_master(master);
+ writel(0, sdd->regs + S3C64XX_SPI_INT_EN);
+
+ free_irq(platform_get_irq(pdev, 0), sdd);
+
destroy_workqueue(sdd->workqueue);
clk_disable(sdd->src_clk);
--
1.7.7.3
^ permalink raw reply related [flat|nested] 6+ messages in thread* [PATCH 3/3] spi/s3c64xx: Implement runtime PM support
2012-01-21 13:24 ` [PATCH 1/3] spi/s3c64xx: Log error interrupts Mark Brown
@ 2012-01-21 13:24 ` Mark Brown
2012-01-21 13:41 ` Bill Gatliff
0 siblings, 1 reply; 6+ messages in thread
From: Mark Brown @ 2012-01-21 13:24 UTC (permalink / raw)
To: Grant Likely, Linus Walleij
Cc: spi-devel-general, linux-samsung-soc, Mark Brown
Enable and disable the clocks to the SPI controller using runtime PM. This
serves the dual purpose of reducing power consumption a little and letting
the core know when the device is idle.
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Heiko Stuebner <heiko@sntech.de>
---
drivers/spi/spi-s3c64xx.c | 39 +++++++++++++++++++++++++++++++++++++++
1 files changed, 39 insertions(+), 0 deletions(-)
diff --git a/drivers/spi/spi-s3c64xx.c b/drivers/spi/spi-s3c64xx.c
index 56dbdf1..b0b843b 100644
--- a/drivers/spi/spi-s3c64xx.c
+++ b/drivers/spi/spi-s3c64xx.c
@@ -25,6 +25,7 @@
#include <linux/clk.h>
#include <linux/dma-mapping.h>
#include <linux/platform_device.h>
+#include <linux/pm_runtime.h>
#include <linux/spi/spi.h>
#include <mach/dma.h>
@@ -782,6 +783,8 @@ static void s3c64xx_spi_work(struct work_struct *work)
while (!acquire_dma(sdd))
msleep(10);
+ pm_runtime_get_sync(&sdd->pdev->dev);
+
spin_lock_irqsave(&sdd->lock, flags);
while (!list_empty(&sdd->queue)
@@ -810,6 +813,8 @@ static void s3c64xx_spi_work(struct work_struct *work)
/* Free DMA channels */
sdd->ops->release(sdd->rx_dma.ch, &s3c64xx_spi_dma_client);
sdd->ops->release(sdd->tx_dma.ch, &s3c64xx_spi_dma_client);
+
+ pm_runtime_put(&sdd->pdev->dev);
}
static int s3c64xx_spi_transfer(struct spi_device *spi,
@@ -892,6 +897,8 @@ static int s3c64xx_spi_setup(struct spi_device *spi)
goto setup_exit;
}
+ pm_runtime_get_sync(&sdd->pdev->dev);
+
/* Check if we can provide the requested rate */
if (!sci->clk_from_cmu) {
u32 psr, speed;
@@ -924,6 +931,8 @@ static int s3c64xx_spi_setup(struct spi_device *spi)
err = -EINVAL;
}
+ pm_runtime_put(&sdd->pdev->dev);
+
setup_exit:
/* setup() returns with device de-selected */
@@ -1164,6 +1173,8 @@ static int __init s3c64xx_spi_probe(struct platform_device *pdev)
mem_res->end, mem_res->start,
sdd->rx_dma.dmach, sdd->tx_dma.dmach);
+ pm_runtime_enable(&pdev->dev);
+
return 0;
err9:
@@ -1197,6 +1208,8 @@ static int s3c64xx_spi_remove(struct platform_device *pdev)
struct resource *mem_res;
unsigned long flags;
+ pm_runtime_disable(&pdev->dev);
+
spin_lock_irqsave(&sdd->lock, flags);
sdd->state |= SUSPND;
spin_unlock_irqrestore(&sdd->lock, flags);
@@ -1277,8 +1290,34 @@ static int s3c64xx_spi_resume(struct device *dev)
}
#endif /* CONFIG_PM */
+#ifdef CONFIG_PM_RUNTIME
+static int s3c64xx_spi_runtime_suspend(struct device *dev)
+{
+ struct spi_master *master = spi_master_get(dev_get_drvdata(dev));
+ struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(master);
+
+ clk_disable(sdd->clk);
+ clk_disable(sdd->src_clk);
+
+ return 0;
+}
+
+static int s3c64xx_spi_runtime_resume(struct device *dev)
+{
+ struct spi_master *master = spi_master_get(dev_get_drvdata(dev));
+ struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(master);
+
+ clk_enable(sdd->src_clk);
+ clk_enable(sdd->clk);
+
+ return 0;
+}
+#endif /* CONFIG_PM_RUNTIME */
+
static const struct dev_pm_ops s3c64xx_spi_pm = {
SET_SYSTEM_SLEEP_PM_OPS(s3c64xx_spi_suspend, s3c64xx_spi_resume)
+ SET_RUNTIME_PM_OPS(s3c64xx_spi_runtime_suspend,
+ s3c64xx_spi_runtime_resume, NULL)
};
static struct platform_driver s3c64xx_spi_driver = {
--
1.7.7.3
^ permalink raw reply related [flat|nested] 6+ messages in thread* Re: [PATCH 3/3] spi/s3c64xx: Implement runtime PM support
2012-01-21 13:24 ` [PATCH 3/3] spi/s3c64xx: Implement runtime PM support Mark Brown
@ 2012-01-21 13:41 ` Bill Gatliff
2012-01-21 14:18 ` Mark Brown
0 siblings, 1 reply; 6+ messages in thread
From: Bill Gatliff @ 2012-01-21 13:41 UTC (permalink / raw)
To: Mark Brown
Cc: Grant Likely, Linus Walleij, spi-devel-general, linux-samsung-soc
Guys:
On Sat, Jan 21, 2012 at 2:24 PM, Mark Brown
<broonie@opensource.wolfsonmicro.com> wrote:
> Enable and disable the clocks to the SPI controller using runtime PM. This
> serves the dual purpose of reducing power consumption a little and letting
> the core know when the device is idle.
What about using autosuspend instead? If a client is doing a lot of
closely-spaced SPI transactions on a relatively flat device tree,
might the resulting runtime suspend/resume overhead between each
transaction become noticeable?
I'm doing runtime PM on several drivers myself, and that question
keeps coming up a lot. Especially for devices that are more
complicated to suspend/resume than this one. But even without the
device-specific overhead, I'm wondering how structure-walking that
goes on behind the pm_runtime() calls might tip the balance of PM
gains the opposite way from what we are seeking.
Not a critique of your patch series per se, but you probably have some
thoughts on all of this too--- and I would love to hear them while
they are still fresh. :)
b.g.
--
Bill Gatliff
bgat@billgatliff.com
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH 3/3] spi/s3c64xx: Implement runtime PM support
2012-01-21 13:41 ` Bill Gatliff
@ 2012-01-21 14:18 ` Mark Brown
0 siblings, 0 replies; 6+ messages in thread
From: Mark Brown @ 2012-01-21 14:18 UTC (permalink / raw)
To: Bill Gatliff
Cc: Grant Likely, Linus Walleij, spi-devel-general, linux-samsung-soc
On Sat, Jan 21, 2012 at 02:41:59PM +0100, Bill Gatliff wrote:
> What about using autosuspend instead? If a client is doing a lot of
> closely-spaced SPI transactions on a relatively flat device tree,
> might the resulting runtime suspend/resume overhead between each
> transaction become noticeable?
It seems very low overhead, particularly in the context of the overhead
of the SPI transactions themselves. I have sometimes wondered if it
might be an idea to just make the core do something along these lines by
default as there should be very few cases where it's important to have
the suspend happen immediately.
^ permalink raw reply [flat|nested] 6+ messages in thread
end of thread, other threads:[~2012-01-21 14:18 UTC | newest]
Thread overview: 6+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2011-12-05 21:01 [PATCH 1/3] spi/s3c64xx: Log error interrupts Mark Brown
2011-12-05 21:01 ` [PATCH 2/3] spi/s3c64xx: Convert to dev_pm_ops Mark Brown
2011-12-05 21:01 ` [PATCH 3/3] spi/s3c64xx: Implement runtime PM support Mark Brown
-- strict thread matches above, loose matches on Subject: below --
2012-01-21 13:23 [PATCH 0/3] spi/s3c64xx diagnostic and PM updates Mark Brown
2012-01-21 13:24 ` [PATCH 1/3] spi/s3c64xx: Log error interrupts Mark Brown
2012-01-21 13:24 ` [PATCH 3/3] spi/s3c64xx: Implement runtime PM support Mark Brown
2012-01-21 13:41 ` Bill Gatliff
2012-01-21 14:18 ` Mark Brown
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